I recently formatted a USB flash drive on my Mac (El-Capitan) and made a bootable Mojave installer drive. It worked great and there were no issues, until I needed to reformat it to use on Windows again. I've formatted the drive as FAT32 with a MBR partition and it reflects as such in the Disk Utility:
For some reason, Windows doesn't even recognise that the drive is inserted into the PC. I'd expect to see a 16GB disk with no mountable volumes, instead I just see the same disk-listings that were there before I inserted the drive.
What frustrates me is that I've got experience with partitions and it's not usually rocket-science. The third image shows a hybrid drive with a MacOS partition (for my Macbook Air) that also contains a exFat partition for my media.
I've done this before many times over but can't, for the life of me, figure out why it's not working on this flash drive. Have I missed something really obvious? Am I losing my mind?